If a non-linguist may venture to comment, your chart is more economical and
theoretically impeccable, but unlike the other one it may not help us understand
what a Greek sentence means. Economy is an advantage in describing phonemes, but
is it useful to apply principles of phonology to semantics like this? Surely
[-past +perf] doesn't account for the value of the future "tense" in any
meaningful way?

This of course brings us back to your interpretation of the futur as perfective
(=aor.) + non-past endings, (which was explained in another post which I have
unfortunately already deleted from my mailbox) and which, I might add, of course
only works as a rule of thumb (this is also true of another example you gave,
the French future, which does *not* = infinitive + avoir in the first and second
persons plural, nor in any person in the case of many verbs such as venir,
devoir etc.). It seems to me your approach runs into trouble on the formal level
as soon as we try and use it for verbs other than LUW and the like, but it runs
into trouble even in dealing with plain old LUW if we expect it to explain
anything (as opposed to just being neat and tidy). Trying now to put my ideas
into order a little,

1. Do you have any reason besides the formal resemblance between the aor. "stem"
and the future "stem" to call the future "perfective" (apart from the desire to
make it fit into a chart with one less column)?

2. Once we have said that the future is perfective and non-past, what do we know
about the future? Doesn't this say everything except what matters, namely that
the future is, um, future?

3. Finally, where is the perfect in these charts? Is there any way of including
it without adding a *fourth* column?